static void
PrintConstantDecl(FILE *f, AST *ast)
{
const char *name = ast->d.string;
AST *expr = NULL;
Symbol *sym;
if (!IsConstExpr(ast)) {
ERROR(ast, "%s is not constant", name);
return;
}
sym = LookupSymbol(name);
if (!sym) {
ERROR(ast, "constant symbol %s not declared??", name);
return;
}
expr = (AST *)sym->val;
if (gl_ccode) {
fprintf(f, "#define %s (", ast->d.string);
PrintConstant(f, expr);
fprintf(f, ")\n");
} else {
fprintf(f, " static const int %s = ", ast->d.string);
PrintConstant(f, expr);
fprintf(f, ";\n");
}
}
static void SymReplaceExprRefs (SymEntry* S)
/* Replace the references to this symbol by a copy of the symbol expression */
{
unsigned I;
long Val;
/* Check if the expression is const and get its value */
int IsConst = IsConstExpr (S->Expr, &Val);
CHECK (IsConst);
/* Loop over all references */
for (I = 0; I < CollCount (&S->ExprRefs); ++I) {
/* Get the expression node */
ExprNode* E = CollAtUnchecked (&S->ExprRefs, I);
/* Safety */
CHECK (E->Op == EXPR_SYMBOL && E->V.Sym == S);
/* We cannot touch the root node, since there are pointers to it.
** Replace it by a literal node.
*/
E->Op = EXPR_LITERAL;
E->V.IVal = Val;
}
/* Remove all symbol references from the symbol */
CollDeleteAll (&S->ExprRefs);
}
int SymIsConst (const SymEntry* S, long* Val)
/* Return true if the given symbol has a constant value. If Val is not NULL
** and the symbol has a constant value, store it's value there.
*/
{
/* Check for constness */
return (SymHasExpr (S) && IsConstExpr (S->Expr, Val));
}
long GetSymVal (SymEntry* S)
/* Return the value of a symbol assuming it's constant. FAIL will be called
** in case the symbol is undefined or not constant.
*/
{
long Val;
CHECK (S != 0 && SymHasExpr (S) && IsConstExpr (GetSymExpr (S), &Val));
return Val;
}
void CheckAssertions (void)
/* Check all assertions */
{
unsigned I;
/* Walk over all assertions */
for (I = 0; I < CollCount (&Assertions); ++I) {
const LineInfo* LI;
const char* Module;
unsigned Line;
/* Get the assertion */
Assertion* A = CollAtUnchecked (&Assertions, I);
/* Ignore assertions that shouldn't be handled at link time */
if (!AssertAtLinkTime (A->Action)) {
continue;
}
/* Retrieve the relevant line info for this assertion */
LI = CollConstAt (&A->LineInfos, 0);
/* Get file name and line number from the source */
Module = GetSourceName (LI);
Line = GetSourceLine (LI);
/* If the expression is not constant, we're not able to handle it */
if (!IsConstExpr (A->Expr)) {
Warning ("Cannot evaluate assertion in module `%s', line %u",
Module, Line);
} else if (GetExprVal (A->Expr) == 0) {
/* Assertion failed */
const char* Message = GetString (A->Msg);
switch (A->Action) {
case ASSERT_ACT_WARN:
case ASSERT_ACT_LDWARN:
Warning ("%s(%u): %s", Module, Line, Message);
break;
case ASSERT_ACT_ERROR:
case ASSERT_ACT_LDERROR:
Error ("%s(%u): %s", Module, Line, Message);
break;
default:
Internal ("Invalid assertion action (%u) in module `%s', "
"line %u (file corrupt?)",
A->Action, Module, Line);
break;
}
}
}
}
int IsConstExport (const Export* E)
/* Return true if the expression associated with this export is const */
{
if (E->Expr == 0) {
/* External symbols cannot be const */
return 0;
} else {
return IsConstExpr (E->Expr);
}
}
void CheckAssertions (void)
/* Check all assertions and evaluate the ones we can evaluate here. */
{
unsigned I;
/* Get the number of assertions */
unsigned Count = CollCount (&Assertions);
/* Check the assertions */
for (I = 0; I < Count; ++I) {
long Val;
/* Get the next assertion */
Assertion* A = CollAtUnchecked (&Assertions, I);
/* Ignore it, if it should only be evaluated by the linker */
if (!AssertAtAsmTime (A->Action)) {
continue;
}
/* Can we evaluate the expression? */
if (IsConstExpr (A->Expr, &Val) && Val == 0) {
/* Apply the action */
const char* Msg = GetString (A->Msg);
switch (A->Action) {
case ASSERT_ACT_WARN:
LIWarning (&A->LI, 0, "%s", Msg);
break;
case ASSERT_ACT_ERROR:
LIError (&A->LI, "%s", Msg);
break;
default:
Internal ("Illegal assert action specifier");
break;
}
}
}
}
int IsConstExpr (ExprNode* Root)
/* Return true if the given expression is a constant expression, that is, one
* with no references to external symbols.
*/
{
int Const;
Export* E;
Section* S;
MemoryArea* M;
if (EXPR_IS_LEAF (Root->Op)) {
switch (Root->Op) {
case EXPR_LITERAL:
return 1;
case EXPR_SYMBOL:
/* Get the referenced export */
E = GetExprExport (Root);
/* If this export has a mark set, we've already encountered it.
* This means that the export is used to define it's own value,
* which in turn means, that we have a circular reference.
*/
if (ExportHasMark (E)) {
CircularRefError (E);
Const = 0;
} else {
MarkExport (E);
Const = IsConstExport (E);
UnmarkExport (E);
}
return Const;
case EXPR_SECTION:
/* A section expression is const if the segment it is in is
* not relocatable and already placed.
*/
S = GetExprSection (Root);
M = S->Seg->MemArea;
return M != 0 && (M->Flags & MF_PLACED) != 0 && !M->Relocatable;
case EXPR_SEGMENT:
/* A segment is const if it is not relocatable and placed */
M = Root->V.Seg->MemArea;
return M != 0 && (M->Flags & MF_PLACED) != 0 && !M->Relocatable;
case EXPR_MEMAREA:
/* A memory area is const if it is not relocatable and placed */
return !Root->V.Mem->Relocatable &&
(Root->V.Mem->Flags & MF_PLACED);
default:
/* Anything else is not const */
return 0;
}
} else if (EXPR_IS_UNARY (Root->Op)) {
SegExprDesc D;
/* Special handling for the BANK pseudo function */
switch (Root->Op) {
case EXPR_BANK:
/* Get segment references for the expression */
GetSegExprVal (Root->Left, &D);
/* The expression is const if the expression contains exactly
* one segment that is assigned to a memory area which has a
* bank attribute that is constant.
*/
return (D.TooComplex == 0 &&
D.Seg != 0 &&
D.Seg->MemArea != 0 &&
D.Seg->MemArea->BankExpr != 0 &&
IsConstExpr (D.Seg->MemArea->BankExpr));
default:
/* All others handled normal */
return IsConstExpr (Root->Left);
}
} else {
/* We must handle shortcut boolean expressions here */
switch (Root->Op) {
case EXPR_BOOLAND:
if (IsConstExpr (Root->Left)) {
/* lhs is const, if it is zero, don't eval right */
if (GetExprVal (Root->Left) == 0) {
return 1;
} else {
return IsConstExpr (Root->Right);
}
} else {
/* lhs not const --> tree not const */
return 0;
}
break;
case EXPR_BOOLOR:
if (IsConstExpr (Root->Left)) {
/* lhs is const, if it is not zero, don't eval right */
if (GetExprVal (Root->Left) != 0) {
return 1;
} else {
return IsConstExpr (Root->Right);
}
} else {
/* lhs not const --> tree not const */
return 0;
}
break;
default:
/* All others are handled normal */
return IsConstExpr (Root->Left) && IsConstExpr (Root->Right);
}
}
}
void DoConditionals (void)
/* Catch all for conditional directives */
{
IfDesc* D;
do {
switch (CurTok.Tok) {
case TOK_ELSE:
D = GetCurrentIf ();
/* Allow an .ELSE */
ElseClause (D, ".ELSE");
/* Remember the data for the .ELSE */
if (D) {
ReleaseFullLineInfo (&D->LineInfos);
GetFullLineInfo (&D->LineInfos);
D->Name = ".ELSE";
}
/* Calculate the new overall condition */
CalcOverallIfCond ();
/* Skip .ELSE */
NextTok ();
ExpectSep ();
break;
case TOK_ELSEIF:
D = GetCurrentIf ();
/* Handle as if there was an .ELSE first */
ElseClause (D, ".ELSEIF");
/* Calculate the new overall if condition */
CalcOverallIfCond ();
/* Allocate and prepare a new descriptor */
D = AllocIf (".ELSEIF", 0);
NextTok ();
/* Ignore the new condition if we are inside a false .ELSE
** branch. This way we won't get any errors about undefined
** symbols or similar...
*/
if (IfCond) {
SetIfCond (D, ConstExpression ());
ExpectSep ();
}
/* Get the new overall condition */
CalcOverallIfCond ();
break;
case TOK_ENDIF:
/* We're done with this .IF.. - remove the descriptor(s) */
FreeIf ();
/* Be sure not to read the next token until the .IF stack
** has been cleanup up, since we may be at end of file.
*/
NextTok ();
ExpectSep ();
/* Get the new overall condition */
CalcOverallIfCond ();
break;
case TOK_IF:
D = AllocIf (".IF", 1);
NextTok ();
if (IfCond) {
SetIfCond (D, ConstExpression ());
ExpectSep ();
}
CalcOverallIfCond ();
break;
case TOK_IFBLANK:
D = AllocIf (".IFBLANK", 1);
NextTok ();
if (IfCond) {
if (TokIsSep (CurTok.Tok)) {
SetIfCond (D, 1);
} else {
SetIfCond (D, 0);
SkipUntilSep ();
}
}
CalcOverallIfCond ();
break;
case TOK_IFCONST:
D = AllocIf (".IFCONST", 1);
NextTok ();
if (IfCond) {
ExprNode* Expr = Expression();
SetIfCond (D, IsConstExpr (Expr, 0));
FreeExpr (Expr);
ExpectSep ();
}
CalcOverallIfCond ();
break;
case TOK_IFDEF:
D = AllocIf (".IFDEF", 1);
NextTok ();
if (IfCond) {
SymEntry* Sym = ParseAnySymName (SYM_FIND_EXISTING);
SetIfCond (D, Sym != 0 && SymIsDef (Sym));
}
CalcOverallIfCond ();
break;
case TOK_IFNBLANK:
D = AllocIf (".IFNBLANK", 1);
NextTok ();
if (IfCond) {
if (TokIsSep (CurTok.Tok)) {
SetIfCond (D, 0);
} else {
SetIfCond (D, 1);
SkipUntilSep ();
}
}
CalcOverallIfCond ();
break;
case TOK_IFNCONST:
D = AllocIf (".IFNCONST", 1);
NextTok ();
if (IfCond) {
ExprNode* Expr = Expression();
SetIfCond (D, !IsConstExpr (Expr, 0));
FreeExpr (Expr);
ExpectSep ();
}
CalcOverallIfCond ();
break;
case TOK_IFNDEF:
D = AllocIf (".IFNDEF", 1);
NextTok ();
if (IfCond) {
SymEntry* Sym = ParseAnySymName (SYM_FIND_EXISTING);
SetIfCond (D, Sym == 0 || !SymIsDef (Sym));
ExpectSep ();
}
CalcOverallIfCond ();
break;
case TOK_IFNREF:
D = AllocIf (".IFNREF", 1);
NextTok ();
if (IfCond) {
SymEntry* Sym = ParseAnySymName (SYM_FIND_EXISTING);
SetIfCond (D, Sym == 0 || !SymIsRef (Sym));
ExpectSep ();
}
CalcOverallIfCond ();
break;
case TOK_IFP02:
D = AllocIf (".IFP02", 1);
NextTok ();
if (IfCond) {
SetIfCond (D, GetCPU() == CPU_6502);
}
ExpectSep ();
CalcOverallIfCond ();
break;
case TOK_IFP4510:
D = AllocIf (".IFP4510", 1);
NextTok ();
if (IfCond) {
SetIfCond (D, GetCPU() == CPU_4510);
}
ExpectSep ();
CalcOverallIfCond ();
break;
case TOK_IFP816:
D = AllocIf (".IFP816", 1);
NextTok ();
if (IfCond) {
SetIfCond (D, GetCPU() == CPU_65816);
}
ExpectSep ();
CalcOverallIfCond ();
break;
case TOK_IFPC02:
D = AllocIf (".IFPC02", 1);
NextTok ();
if (IfCond) {
SetIfCond (D, GetCPU() == CPU_65C02);
}
ExpectSep ();
CalcOverallIfCond ();
break;
case TOK_IFPSC02:
D = AllocIf (".IFPSC02", 1);
NextTok ();
if (IfCond) {
SetIfCond (D, GetCPU() == CPU_65SC02);
}
ExpectSep ();
CalcOverallIfCond ();
break;
case TOK_IFREF:
D = AllocIf (".IFREF", 1);
NextTok ();
if (IfCond) {
SymEntry* Sym = ParseAnySymName (SYM_FIND_EXISTING);
SetIfCond (D, Sym != 0 && SymIsRef (Sym));
ExpectSep ();
}
CalcOverallIfCond ();
break;
default:
/* Skip tokens */
NextTok ();
}
} while (IfCond == 0 && CurTok.Tok != TOK_EOF);
}
